It is not uncommon, when listening to a radio while in a vehicle, for the radio signal to be intermittently lost. For example, when traveling around a mountainous area, a radio signal can be lost until the vehicle moves into an area where there is no blockage of the radio signal by the mountains. It is common that the same program content is transmitted by different transmitting stations/towers located on different sides of the mountain to accommodate different listening audiences. However, unless the person in the vehicle knows of the alternate transmitting station and knows to which frequency to tune, the occupant of the vehicle will not be able to listen to the content as she is traversing the obstacle.
In a different but related scenario, a person traveling in a vehicle, such as a bus, train, car, plane, or boat may travel so much that she would be unable to listen to program content of a favorite radio station because the vehicle movement takes the listener away from the finite range of the transmitting station. If the program content is carries by an affiliate radio station in an adjoining area, then the listener may be able to manually retune her radio receiver to the new frequency if she were aware of the affiliate station and its differing frequency.